A control system for a liquid motion lamp maintains the proper temperature of liquids within the lamp to provide desired motion within the lamp, and reduces sensitivity to ambient temperature. The lamp preferably includes two heating elements, a first element for initial heating, such as a heat blanket, resistive glass coating, or a submerged ring, and a second heating element generally providing both heat and lighting. A sensor measures the temperature of the liquid inside the lamp and the control system controls the heat sources to maintain the temperature within operating limits.